In general, a conventional ball valve gasket is installed between a valve and a ball to provide a slide assisting effect during the use of the ball valve gasket, and the conventional gasket is mainly divided into two types, respectively: a metal gasket and a non-metal gasket.
However, the non-metal gasket comes with less strength and rigidity and thus may be damaged easily when it is used under the conditions of high temperature and high pressure for a long time. On the other hand, although the metal gasket can overcome the aforementioned drawback of the non-metal gasket, the metal gasket and the ball are rubbed with each other, so that the gasket and the ball may be worn out or damaged easily. In addition, such gasket cannot be replaced by itself, but it is necessary to replace the whole set of gasket and ball in order to maintain the air tightness effectively. Obviously, the non-metal or metal gasket cannot meet the requirement for the slide assisting effect or achieve the effects of extending the service life of the gasket or installing and removing the gasket easily. In addition, the manufacture of the metal gasket requires a more complicated procedure and takes a longer time.
Therefore, it is a main subject of the present invention to provide a ball valve gasket structure that can achieve the slide assisting effect, improve service life, and facilitate installation, disassembly and manufacture.